Among the 26 tumor entities that were investigated in the present study, 7 tumor types (glioblastomas, anaplastic thyroid carcinomas, gastric cancer, colon cancer, renal clear cell carcinomas, testicular cancer, and malignant melanomas) were evaluated for SST4 expression at the protein level for the first time. This evidence concerns the gene SSTR4 and thyroid gland undifferentiated (anaplastic) carcinoma.